A federal appeals court ruling underscores why Colorado lawmakers should pass House Bill 1309, pending in the state Senate.

The immediate issue involves an air pollution rule called new source review, but the broader concern is that Colorado should have flexibility to protect its own public health and environment.

Last year, the Bush administration rolled back 30 years of new source review policy, which required older industrial facilities to install modern air pollution controls anytime they expanded or renovated. The policy substituted an economic test. For instance, it required pollution-control updates only if the cost of equipment modifications exceeded 20 percent of an electric generating unit’s replacement value.

Several states challenged the rollbacks because they clearly would increase air pollution. In fact, federal law lets states adopt air pollution rules that are stricter than federal ones. But Colorado meekly followed along, because Colorado law forbids the state’s health agency from adopting pollution rules tougher than federal standards.

Last Friday, the U.S. Court of Appeals in Washington, D.C., said the Bush administration’s rollbacks violate federal law. The Clean Air Act requires updated pollution controls for “any physical change” at an industrial facility. But the administration claimed the word “any” doesn’t mean “any” and instead insisted that there could be many exceptions. The three-judge appeals panel unanimously ripped the shoddy logic. “Only in a Humpty Dumpty world,” the court said, could a federal agency “ignore an expansive word that Congress” used.

So at this point, the federal rule Colorado regulators said they were obligated to follow is in limbo. If industries in Colorado plan to expand, they may not know what rules to obey, unless our legislature uses the flexibility in federal law to protect our state’s public health.

HB 1309 would let Colorado agencies adopt air pollution rules that are tougher than federal ones. HB 1309 passed the House, where it was sponsored by Rep. Anne McGihon, D-Denver. On Wednesday, the bill will be heard by the Senate’s State, Veterans and Military Affairs Committee, where its sponsor is Sen. Dan Grossman, also a Denver Democrat.

Colorado’s air will improve if older industries update pollution controls when they expand or renovate. But the dust-up over new source review is just one of many possible situations where the state should be able to act regardless of what the feds do. It’s absurd for Colorado to deny itself the flexibility that Congress gave states. The legislature should pass HB 1309.